PRACTICAL ASPECTS OF LOW-FLOW FREQUENCY-ANALYSIS

Abstract

This paper considers some practical aspects concerning the application of the Weibull distribution to low‐flow frequency analysis. Two‐ and three‐parameter forms of the distribution are fitted to a total of 987 distributions derived from the daily flow data of 134 catchments located in southeastern Australia. The relative performance of three estimation methods (moments, maximum likelihood, and probability weighted moments) is investigated, and it is found that the different estimation methods provide distinct sets of quantile estimates. The method of probability weighted moments is more likely to give unsatisfactory estimates of the smallest drought and in general tends to yield less severe..